Abstract: A method for authenticating a printer consumable in which an encrypted random number and its first signature are passed from a printer authentication chip to a consumable authentication chip, in the consumable chip: the encrypted random number and first signature are decrypted; a second signature of the random number is calculated and compared with the first signature to produce a match at which a first number produced by encrypting the random number and a memory vector is passed to the printer chip, and in the printer chip, a second number is produced by encrypting the random number and memory vector and compared with the first number to produce a match and valid consumable chip, or a mismatch and invalid consumable chip. The memory vector comprises updatable consumable state data whose manner of updating is protected by requiring clearing of the memory vector when change of the updating manner is attempted.

Abstract: A region having coded data thereon, wherein at least some of the coded data includes data indicative of a functional attribute of a part of the region. A sensing device for use with such a region, the sensing device for sensing and reacting to data indicative of a functional attribute of a part of the region.

Abstract: A method and system for enabling user interaction with computer software running in a computer system. A user is provided with an interface surface containing information relating to the computer software and including coded data indicative of an identity of the interface surface and of at least one reference point of the interface surface. The user places a sensing device into an operative position relative to the interface surface. In this operative position, the sensing device senses indicating data indicative of: the identity of the interface surface; and a position of the sensing device relative to the interface surface, using at least some of the coded data. The computer system receives the indicating data from the sensing device, and uses the indicating data to identify at least one interactive element relating to the computer software. The computer software is then operated in accordance with instructions associated with the at least one interactive element.

Abstract: A sensing device for generating orientation data when positioned or moved relative to a surface, the orientation data being indicative of an orientation of the sensing device relative to the surface, the surface having coded data disposed upon it, the coded data being indicative, when sensed by the sensing device, of the orientation, the sensing device including: a housing; orientation sensing means configured to generate the orientation data using at least some of the coded data; and communications means configured to communicate the orientation data to a computer system.

Abstract: The invention enables a user to obtain a document associated with the program content of a video signal. Coded data on a surface is read by a sensing device which generates indicating data which is a request for the document. A computer system receives the indicating data from the sensing device and extracts document identity data from the video signal, in order to retrieve the document.

Abstract: A method of conferencing between two or more remote conference participants via an interactive conference form is provided.

Abstract: The invention enables a user to obtain a document associated with the program content of a video signal. Coded data on a surface is read by a sensing device which generates indicating data which is a request for the document. A computer system receives the indicating data from the sensing device and extracts document identity data from the video signal, in order to retrieve the document.

Abstract: A region defined in relation to a surface, and a method for defining such a region; coded data being disposed within the region, the coded data being indicative of an identity of the region and of a plurality of points within the region; in one embodiment, the coded data comprising a plurality of tags, each tag being indicative of the region identity and of its own position within the region.

Abstract: A sensing device for generating orientation data when positioned or moved relative to a surface, the orientation data being indicative of an orientation of the sensing device relative to the surface, the surface having coded data disposed upon it, the coded data being indicative, when sensed by the sensing device, of the orientation, the sensing device including: a housing; orientation sensing means configured to generate the orientation data using at least some of the coded data; and communications means configured to communicate the orientation data to a computer system.

Abstract: A region defined in relation to a surface, and a method for defining such a region; coded data being disposed within the region, the coded data being indicative of an identity of the region and of a plurality of points within the region; in one embodiment, the coded data comprising a plurality of tags, each tag being indicative of the region identity and of its own position within the region.

Abstract: A method and system for enabling user interaction with computer software running in a computer system. A user is provided with an interface surface containing information relating to the computer software and including coded data indicative of an identity of the interface surface and of at least one reference point of the interface surface. The user places a sensing device into an operative position relative to the interface surface. In this operative position, the sensing device senses indicating data indicative of: the identity of the interface surface; and a position of the sensing device relative to the interface surface, using at least some of the coded data. The computer system receives the indicating data from the sensing device, and uses the indicating data to identify at least one interactive element relating to the computer software. The computer software is then operated in accordance with instructions associated with the at least one interactive element.

Abstract: A sensing device for generating orientation data when positioned or moved relative to a surface, the orientation data being indicative of an orientation of the sensing device relative to the surface, the surface having coded data disposed upon it, the coded data being indicative, when sensed by the sensing device, of the orientation, the sensing device including: a housing; orientation sensing means configured to generate the orientation data using at least some of the coded data; and communications means configured to communicate the orientation data to a computer system.

Abstract: A region having coded data thereon, wherein at least some of the coded data includes data indicative of a functional attribute of a part of the region. A sensing device for use with such a region, the sensing device for sensing and reacting to data indicative of a functional attribute of a part of the region.

Abstract: A method and system for enabling user interaction with computer software running in a computer system. A user is provided with an interface surface containing information relating to the computer software and including coded data indicative of an identity of the interface surface and of at least one reference point of the interface surface. The user places a sensing device into an operative position relative to the interface surface. In this operative position, the sensing device senses indicating data indicative of: the identity of the interface surface; and a position of the sensing device relative to the interface surface, using at least some of the coded data. The computer system receives the indicating data from the sensing device, and uses the indicating data to identify at least one interactive element relating to the computer software. The computer software is then operated in accordance with instructions associated with the at least one interactive element.